Chlorine-containing compounds such as chlorofluorocarbons (CFCs) are considered to be detrimental to the Earth's ozone layer. Therefore, compounds that do not damage the environment, but also possess the properties necessary to function as refrigerants, solvents, cleaning agents, foam blowing agents, aerosol propellants, heat transfer media, dielectrics, fire extinguishing agents, sterilants and power cycle working fluids, have been investigated. Fluorinated olefins, especially those containing one or more hydrogens in the molecule (referred to herein as hydrofluoroolefins (HFOs)) are being considered for use in some of these applications, such as in refrigeration as well as in processes to make fluoropolymers. In particular, trans-1,1,1-trifluoro-3-chloro-2-propene (1233zd(E)) is a potential refrigerant and foam blowing compound that has negligible ozone depletion potential (ODP) and low global warming potential (GWP). In fact, 1233zd(E)'s ODP has been measured as 0.00034.
1233zd(E) feedstock is usually contaminated with carbon tetrachloride, however, which is one of the precursor compounds to 1,1,1,3,3-pentachloropropane (240fa). In a fluorination reactor, the carbon tetrachloride will fluorinate to R11. R11 has a boiling point of 23.8° C. and 1233zd(E) has a boiling point of 18.5° C. Attempts to separate R11 from 1233zd(E) by distillation were unsuccessful, indicating the presence of an azeotrope or near azeotrope. A contaminant, such as R11, which has an ODP of 1.0, can greatly decrease the ozone depletion potential of the compound. For example, if 1233zd(E) is contaminated with merely 1000 ppm of R11, its ODP would increase from 0.00034 to 0.00134. Accordingly, there remains a need for 1233zd(E) in uncontaminated or purified form and a separation method by which to produce it.